1952 IWC Mark XI (Ref. 6B/346) "RAF Issued"

The Mk. XI was a watch born out of rigorous specifications and necessity. As the British Ministry of defense came to realize after the issuance of the famed “Dirty Dozen” timepieces, they came to the conclusion that these watches just weren’t accurate or durable enough for their pilots. So in 1947, the British Ministry of Defense created the 6B/346 navigation watch standard which became known as Mk. XI.

Both IWC and JLC produced watches under the 6B/346 specification. The JLC Mk. XI was discontinued in 1953 and IWC then become the sole supplier, outfitting RAF Pilot’s until the watches were decommissioned in 1981.

The Mk. XI’s were initially produced with radium dials however it’s almost impossible to find them with their original dials as they were serviced every year, and as time went on the MOD’s specifications required improvements. Such as the use of tritium, which is why the IWC Mk. XI's seen today featured the matte black “circle-t” dials that have become synonymous with British military watches and indicate the use of tritium as the luminous material.


Brand IWC
Style Mk. XI
Model 6B/346
Serial 174
Size Men's
Material SS
Dial Matte Black 
Millimeters 36mm
Bracelet Fixed Black Leather Strap


The fixed spring bar case has been previously polished and is in excellent condition and shows minimal signs of previous use. The stepped bezel shows light signs of use and is in overall wonderful condition. The unsigned crown is believed to remain original to the watch. The case back displays all of its military markings in deep legible condition. The watch comes supplied on a fixed black leather strap, which may have been placed on the watch during a prior military service interval.


The matte black dial in remarkably well-preserved condition, only showing light aging around the edges of the dial. The white Arabic numerals and text are in excellent condition. The tritium markers have aged to a beautiful creamy yellow coloration and exhibit no degradation when inspected under U.V. light. The tritium hands have aged to match the dial, and show no degradation when inspected under U.V. light.


None. Watch is keeping time perfectly, previous service history is unknown.